Certain polysubstituted benzothiazoles

ABSTRACT

IN WHICH R is CN or a radical of the formula   Substituted benzthiazoles of the general formula

United States Patent [19] Wagner et al.

[4 1 Dec. 3,19%

[ CERTAIN POLYSUBSTITUTED BENZOTHIAZOLES [75] Inventors: Klaus Wagner, Cologne; Hans Scheinpflug; Paul-Ernst Frohberger, both of Leverkusen, all of Germany [73] Assignee: Bayer Alttiengesellschaft,

Leverkusen, Germany [22] Filed: July 10, 1972 I 21 App]. No.: 270,391

[30] Foreign Application Priority Data July 23, l97l Germany 2136923 [52] US. Cl 260/304, 260/247.l, 260/293.57,

424/248, 424/267, 424/270 [51] Int. Cl C07d 91/44 [58] Field of Search 260/304, 247.1, 293.57

[56] References Cited UNITED STATES PATENTS 9/1972 Wagner et al. 260/304 OTHER PUBLICATIONS Lee et al., Chem. Abstracts, 76: 1/498p (1972).

Primary ExaminerRichard J. Gallagher Attorney, Agent, or Firm-Burgess, Dinklage & Sprung [57] ABSTRACT Substituted benzthiazoles of the general formula R l W in which R is CN or a radical of the formula COZ,

R is halogen, nitro, trifluoromethyl,

trifluoromethoxy or a radical of the formula -SO -Y,

R is hydrogen, halogen, trifluoromethyl,

trifluoromethoxy, nitro, lower alkyl, CN or a radical or the formula CO-Z, n is 0, l or 2, and Y and Z each independently is hydrogen, alkyl, cycloalkyl or alkoxy with up to 6 carbon atoms, aralkyl or aryl, or a radical or the formula 7 Claims, No Drawings CERTAIN POLYSUBSTIITUTED BENZOTHHAZOLES The present invention relates to and has for its objects the provision of particular new substituted benzthiazoles, i.e. 2-cyano-, -acyl-, -alkoxycarbonyl-or -aminocarbonyl-benzthiazoles which may be further substituted, which possess fungicidal bactericidal, insecticidal, acaricidal and algicidal properties, active compositions in the form of mixtures of such compounds with solids and liquid dispersible carrier vehicles, and methods for producing such compounds and for using such compounds in a new way especially for combating pests, e.g., fungi, bacteria, insects, acarids and algae, especially fungi and bacteria, with other and further objects becoming apparent from a study of the within specification and accompanying examples.

It has long been known to use zinc ethylene-1,2-bisdithiocarbamate (Compound A) and N- trichloromethyl-thiotetrahydrophthalimide (Compound B) as fungicides in agriculture (including horticulture); these compounds are important commercial products (cf. R. Wegler, Chemie der Pflanzenschutzund Schadlingsbekampfungsmittel, Volume 2, pages 65 and 108, Berlin/Heidelberg/New York 1970)). The

activity in the case of low applied concentrations, however, is not always satisfactory. The present invention provides substituted benz' thiazoles of the general formula in which R is CN or a radical of the formula -COZ,

R is halogen, nitro, trifluoromethyl, trifluoromethoxy or a radical of the formula R is hydrogen, halogen, trifluoromethyl, trifluoromethoxy, nitro, lower alkyl, CN or a radical of the formula n is 0, l or 2, and

Y and Z each independently is hydrogen, alkyl, cycloalkylor alkoxy with up to 6 carbon atoms, aralkyl or aryl, or a radical of the formula in which R and R each independently is hydrogen, alkyl or alkoxyalkyl with up to 12 carbon atoms, lower alkenyl, or phenylalkyl or phenyl wherein the phenyl may be substituted by chlorine, bromine, trifluoromethyl or methyl, or R and R, together with the attached nitrogen atom, form a 5- or 6-membered heterocyclic ring.

Preferably, R is chlorine, bromine, nitro, trifluoromethyl or --SO --Y; R is methyl, ethyl, chlorine, bromine, cyano, trifluoromethyl, nitro or -CO-Z; Y and Z each independently is lower alkyl or alkoxy with up to 4 carbon atoms, benzyl, phenyl or in which R and R each independently is hydrogen, alkyl or cycloalkyl with up to 6 carbon atoms or one of R and R may be phenyl, or R 'and R together with the connecting nitrogen atom form a 5- or 6-membered heterocyclic ring which may additionally contain in the hetero ring oxygen, sulfer or an Nlalkyl group, especially a pyrrolidine or piperidine or morpholine ring.

The invention also provides a process for the production of a substituted benzthiazole of the formula (I) in which a benzthiazole-N-oxide of the general formula in which R, R, R and n have the meanings stated above, is reduced with either (a) a trivalent phosphorus compound of the general formula N02 (IV) Some of the benzthiazole-N-oxides required as starting materials, defined by the formula (II), and their preparation are known, e.g. German DOS 1,904,653; thecompounds which are still new can be obtained in corresponding manner from l-halogen-Z-nitrobenzene derivatives and thioglycolic acid derivatives in water or an organic solvent, e.g. alcohol or benzene, in the presence of a base, e.g. triethylamine.

The trivalent phosphorus reducing agents, defined by the general formula (III), are generally known. In formula (III) R preferably is chlorine, bromine, ethoxy, phenyl or phenoxy.

The process of the invention may be carried out in the presence of an inert diluent. As diluent, inert organic solvents are suitable. These include hydrocarbons, such as benzene, and chlorinated hydrocarbons, such as methylene chloride, chloroform, carbon tetrachloride and ethylene chloride.

The reaction temperatures can be varied within a fairly wide range. In general, the reaction is carried out at from about -20 to +100C, preferably about 0 to 60C.

When carrying out the process according to the invention, the benzthiazole-N-oxides may be provided in an inert solvent and reduction may be effected with approximately the equimolar amount of the reducing agent; the latter may often be used in excess, e.g. up to about 50 percent. Working up may take place by drawing off the solvent, washing the residue with water, and recrystallization from an appropriate solvent.

Those compounds of the formula (I) in which there is a chlorine atom in 4-position are preferably obtained from the correspondingly substituted benzthiazole-N- oxides by reaction with thionyl chloride at a temperature from about 20 to 160C, preferably about 50 to 110C as described in application Ser. No. 271,886 filed July 14, 1972.

The active compounds according to the invention exhibit a strong fungitoxic and bacteriotoxic activity. In the concentrations necessary for the control of fungi and bacteria, they generally do not damage cultivated plants and they have a low toxicity'to warm-blooded animals. For these reasons they are suitable for use as crop protection agents for the control of fungi and bacteria. Fungitoxic agents in crop protection are used for the control of Archimycetes, Phycomycetes, Ascomycetes, Basidiomycetes and Fungi Imperfecti.

The active compounds according to the invention have a very broad activity spectrum and can be applied against parasitary fungi and bacteria which infect ab0ve-the-soil parts of plants or attack the plants from the soil, and seed-borne pathogenic agents.

The active compounds according to the invention have given especially good results in the control of rice diseases. Thus, they show an excellent activity against the fungus Piricularia oryzae.

The active compounds are likewise highly effective and of particular practical importance when they are used as seed dressings or soil treatment agents against phytopathogenic fungi which adhere to the seed or occur in the soil and cause, in cultivated plants, seedlings diseases, root rots, tracheomycoses, stem, stalk, leaf, blossom, fruit or seed diseases, such as Tilletia caries, Helminthosporium gramineum, Fusarium nivale, Fusarium culmorum, Rhizoctonia solani, Phialophora cinerescens, Verticillium alboarrum, Fusarium dianthi, Fusarium cubense, Fusarium oxysporum, Fusarium solani, Sclerotinia sclerotiorum, Thielaviopsis basicola and Phytophthora cact0rum..

The active compounds according to the invention have e.g. also proved effective against Pellicularia sasakii, Cochliobolus mivabeanus, Mycosphaerella musicola, Cercospora personata, Botrytis cinerea, Collectotrichum coffeanum and Alternaria species. Bacteria species such as Xanthomonas oryzae can also be controlled.

The active compounds according to the instant invention can be utilized, if desired, in the form of the usual formulations or compositions with conventional inert (i.e., plant compatibleor herbicidally inert) pesticide diluents or extenders, i.e., diluents, carriers or extenders of the type usable in conventional pesticide formulations or compositions, e.g. conventional pesticide dispersible carrier vehicles such as gases, solutions, emulsions, suspensions, emulsifiable concentrates, spray powders, pastes, soluble powders, dusting agents, granules, etc. These are prepared in known manner, for instance by extending the active compounds with conventional pesticide dispersible liquid diluent carriers and/or dispersible solid carriers optionally with the use of carrier vehicle assistants, e.g. conventional pesticide surface-active agents, including emulsifying agents and/or dispersing agents, whereby, for example, in the case where water is used as diluent, organic solvents may be added as auxiliary solvents. The following may be chiefly considered for use as conventional carrier vehicles for this purpose: aerosol propellants which are gaseous at normal temperatures and pressures, such as freon; inert dispersible liquid diluent carriers, including inert organic solvents, such as aromatic hydrocarbons (e.g. benzene, toluene, xylene, alkyl naphthalenes, etc.), halogenated, especially chlorinated, aromatic hydrocarbons (e.g. chlorobenzenes, etc.), cycloalkanes, (e.g. cyclohexane, etc.), paraffms (e.g. petroleum or mineral oil fractions), chlorinated aliphatic hydrocarbons (e.g. methylene chloride, chloroethylenes, etc.), alcohols (e.g. methanol, ethanol, propanol, butanol, glycol, etc.) as well as ethers and esters thereof (e.g. glycol monomethyl ether, etc.), amines (e.g. ethanolamine, etc.), amides (e.g. dimethyl formamide, etc.), sulfoxides (e.g. dimethyl sulfoxide, etc.), acetonitrile, ketones (e.g. acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), and/or water; as well as inert dispersible finely divided solid carriers, such as ground natural minerals (e.g. kaolins, clays, alumina, silica, chalk, i.e. calcium carbonate, talc, attapulgite, montmorillonite, kieselguhr, etc.) and ground synthetic minerals (e.g. highly dispersed silicic acid, silicates, e.g. alkali silicates, etc.); whereas the following may be chiefly considered for use as conventional carrier vehicle assistants, e.g. surface-active agents, for this purpose: emulsifying agents, such as non-ionic and- /or anionic emulsifying agents (e.g. polyethylene oxide esters of fatty acids, polyethyleneoxide ethers of fatty alcohols, alkyl sulfates, alkyl sulfonates, aryl sulfonates, etc., and especially alkyl arylpolyglycol ethers, magnesium stearate, sodium oleate, etc.); and/or dispersing agents, such as lignin, sulfite waste liquors, methyl cellulose, etc.

Such active compounds may be employed alone or in the form of mixtures with one another and/or with such solid and/or liquid dispersible carrier vehicles and/or with other known compatible active agents, especially plant protection agents, such as other fungicides, bactericides, insecticides, acaricides, and algicides, or rodenticides, nematocides, herbicides, fertilizers, growthregulating agents, etc., if desired, or in the form of particular dosage preparations for specific application made therefrom, such as solutions, emulsions, suspensions, powders, pastes, and granules which are thus ready for use.

As concerns commercially marketed preparations, these generally contemplate carrier composition mixtures in which the active compound is present in an amount substantially between about 0.1-95% by weight, and preferably O.590% by weight, of the mixture, whereas carrier composition mixtures suitable for direct application or field application generally contemplate those in which the active compound is present in an amount substantially between about 0.000140%, preferably 0.0ll%, by weight of the mixture. Thus, the present invention contemplates over-all compositions which comprises mixtures of a conventional dispersible carrier vehicle such as (l) a dispersible inert finely divided carrier solid, and/or (2) a dispersible carrier liquid such as an inert organic solvent and/or water preferably including a surface-active effective amount ofa carrier vehicle assistant, e.g. a surface-active agent,

one of fungi and bacteria, which comprises applying to at least one of correspondingly (a) such fungi, (b) such bacteria, (c) such insects, (d) such acarids, (e) such algae, and (f) the corresponding habitat thereof, i.e. the locus to be protected, a correspondingly combative or toxic amount, i.e. a fungicidally, bactericidally, insecticdally, acaricidally, or algicidally effective amount of the particular active compound of the invention alone or together with a carrier vehicle as noted above. The instant formulations or compositions are applied in the usual manner, for instance by spraying, atomizing, vaporizing, scattering, dusting, watering, squirting, sprinkling, pouring, fumigating, and the like.

it will be realized, of course, that the concentration of the particular active compound utilized in admixture with the carrier vehicle will depend upon the intended application. Therefore, in special cases it is possible to go above or below the aforementioned concentration ranges.

The synthesis, unexpected superiority and outstanding activity of the particular new'compounds of the present invention are illustrated, without limitation, by the following examples:

EXAMPLE 1 M ycelium growth test Nutrient medium used:

20 parts by weight agar-agar 200 parts by weight potato dccoction 5 parts by weight malt 15 parts by weight dextrose 5 parts by weight peptone 2 parts by weight Na HPO,

0.3 parts by weight 10g, preferably about 0.5 to 5g, per kg of seed. For soil treatment, amounts of active compound of aboutl to 500g, preferably about to 200 g, per cubic meter of soil are generally required.

The active compounds can also be used in accordance with the well known ultra-low-volume process with good success, i.e. by applying such compound if normally a liquid, or by applying a liquid composition containing the same, via very effective atomizing equipment, in finely divided form, e.g. average particle diameter of from 50-l 00 microns, or even less, i.e. mist form, for example by airplane crop spraying techniques. Only up to at most about a few liters/hectare are needed, and often amounts only up to about to 1000 g/hectare, preferably to 600 g/hectare, are sufficient. in this process it is possible to use highly concentrated liquid compositions with said liquid carrier vehicles containing from about 20 to about 95% by weight of the active compound or even the 100% active substance alone, e.g. about 20-l00% by weight of the active compound.

Furthermore, the present invention contemplates methods of selectively killing, combating or controlling pests, e.g. fungi, bacteria, insects, acarids and algae.

and more particularly methods of combating at least The amount of active compound :required for the desired concentration of active compound in the nutrient medium is mixed with the stated amount of solvent. The concentrate is thoroughly mixed in the stated proportion with the liquid nutrient medium which has been cooled to 42C and is then poured into Petri dishes of 9 cm diameter. Control dishes to which the preparation has not been added are also set up.

When the nutrient medium has cooled and solidified, the dishes are inoculated with the species of fungi stated in the Table and incubated at about 21C.

Evaluation is carried out after 4-10 days, dependent upon the speed of growth of the fungi. When evaluation is carried out the radial growth of the mycelium on the treated nutrient media is compared with the growth on the control nutrient media. In the evaluation of the fungus growth, the following characteristic values are used:

0 no fungus growth 1 very strong inhibition of growth 2 medium inhibition of growth 3 slight inhibition of growth 4 growth equal to that of untreated control.

The active compounds. their concentrations and the results obtained can be seen from Table l:

TABLE 1 Mycolium growth Lost Fungi Concmtration of Phiulo- Vorti- Cochli- Collectonctive Piricuphora Pellicu- Mycocillium Fusurobulus trichum Xanthocompound, 1min cinerlm'iu sphaorella alboium miyacofiemoms Active compounds p.p.m. ryzae (scans sasakii musicolo atrum dianthi beanus mum oryzne A... CHaCHNHCS-S 10 0 4 3 1 4 4 4 4 4 /Zn CH NHCSS (known).

26." r C N 10 0 1 0 0 3 0 28..- NC N 10 0 0 0 0 0 0 CN JJFa ("J1 33. F C N 10 0 CI 0 0 3 0 O -CN J CI- |N DIN-'- |I I S CONH2 FaC- N SLCONH2 FaC N S LC O-NH-CHa EXAMPLE 2 Agar plate test Test for fungitoxic effectiveness and breadth of the activity spectrum.

Solvent: Acetone Parts by weight: a) 1000 b) 100 To produce a suitable preparation of the active compound, 1 part by weight of the active compound is and active compound has solidified, test fungi from pure cultures are inoculated on to it in small discs of mm diameter. The Petri dishes remain at 20C for 3 days for incubation.

After this time, the inhibiting action of the active compound on the mycelium growth is determined in categories, taking into account the untreated control.

0 means no mycelium growth, either on the treated substrate or on the inoculum; the symbol means mytakeh "P in the Stated of Solvehtcelium growth on the inoculum only, no'spread to the 9 Potato dehtrose agar whlch has h q hy treated substrate; and the symbol means mycelium heahhg lhere added the Preparahoh f the achve growth from the inoculum on to the treated substrate, Compound Such an amouht that the deslred coflcerlsimilar to the spread to the untreated substrate of the tration of active compound IS set up therein. After thort L ough shaking to achieve a uniform dlspersion of the ac- 15 Th ti u d the concentration of the acnve compoun the g is poured mto Petrl dishes tive compounds, the test fungi and the inhibition effects under sterile conditions. When the mixture of substrate hi d can b n from the following Table:

new 2 Agar plate test Concentration of active compound Scleroin the sub- Cortitim'a Thicla- Phyto- Fusarium strate in eimn sclrrozz'opsz's phthom Fusarium Fusarimn solanz' f. Active compound mgJlitre roUsii tiorum basz'cola ractorum culmorum oxysporum pm Unt1"eated. .l -l

A S (a) 10 ll (b) 100 0 0 0 CHz-NHCS Zn cHzNH-fis (known).

2a. (or 10 0 0 no 1lT Y (b) 100 0 0 0 0 0 0 0 \S/CN 2s (a) 10 o n N( (b) 100 0 0 0 0 o o 0 CN N62 27 (a) 10 0 0 0 0 0 0 0 OQN- *U D) 100 o 0 0 0 0 0 o as 01 (a) 10 0 o 0 0 l (b) 100 0 0 0 0 FaC- TI c.

(a) 10 0 i I j v 0 0 c1- fi1 (b) o t i 0 0 s CN TABLE 2-Continuod Concentration of active compound Scleroin the sub- Cortitinia 'Ihiela- 1' h 1 Ln- Fusarium struto in cium sclcrovirmsis phthom F'usnrium Fusnrium solmzz' f. Active compound nip/litre Tolfsii tiorum basicola ('rzctorum culmorum m'g sporumpisi 35 G1 (a) 10 O 0 0 l (b) 100 0 0 0 0 0 Cl- --1l 'I s -CN 34 G1 (a) 0 0 0 (b) 100 0 0 0 O 0 0 0 OQN- II II (l F3 v (It) 10 0 O2N N (b) 100 0 0 0 0 0 0 31 .r (n) 10 ll ll:()-() 0-- PH] (h) 100 (l (l (l (l 0 (l N n 32 (a) 10 0 O FaC- -'N (b) 100 0 0 0 0 0 O 0 F3 G1 (a) 10 l (b) 100 0 O2N HI \S/CONH2 EXAMPLE 3 greenhouse at temperatures of 22 to 24C and a relative atmospheric humidity of about 70% until they are dry. They are then inoculated with an aqueous suspen- Piricularia test: liquid preparation of active compound slon of loovoooito 200,000 Spores/ml 2 Plnculana y' Solvent: 1.9 parts by weight DMF zae and placed in a chamber at 24-26 C and 100% rel- Dispersing agent: 0.1 part by weight- Water: 98 parts by weight water atwe atmosphenc humldlty 5 days after inoculation, the infection of all the leaves present at the time of inoculation is determined as a The amount of active compound requi ed fo the epercentage of the untreated but also inoculated control sired concentration in the spray liquor is mixed with the plants. 0% m ans no infection; 100% means that the stated amount of solvent, and the concentrate is diluted i f ti i tl as great i th case f the nt l with the stated amount of water containing the stated plants. dispersing agent. The active compounds, the concentrations of the ac- 30 rice plants about 14 days old are sprayed with the tive compounds and the results can be seen from the spray liquor until dripping wet. The plants remain in a following Table:

Infection as a percentage of the infection of the untreated control with a concentration of active ctfimpound (in percent) FaC EXAMPLE 4 Bacteria test: Xanthomonas oryzag Solvent: 19 parts by weight dimethyl formamide Dispersing agent: 0.l part by weight alkylarylpolyglycol ether 98 parts by weight Water:

The amount of active compound necessary for the desired concentration of active compound in the spray liquor is mixed withthe stated amount of the solvent and of the dispersing agent, and the concentrate is diluted with the stated amount of water.

ously treated with the preparation is determined as a percentage of the untreated but likewise inoculated leaves of the control plants. 0% denotes no infection; 100% means that the infection is exactly as great as in the case of the control plants.

The active compounds, the concentrations of active compound and the results can be seen from the following Table:

TABLE;

Bacteria test/Xanthomonas Org Zoe Infection as a percentage of the infection of the untreated control with a concentration of active compound (in percent) Active compound 0. 05 0.025

NC --IIT S) OONH2 23 (Ill 26 OzN \Sj-C0NHC2E5 aC I| I OzN N 12 I 38 50 FaC -N SLCONH2 l CF EXAMPLE 5 Seed dressing test/bunt of wheat (seed-borne mycosis) compound.

Wheat seed is contaminated with 5 g of the chlamydospores of Tilletia tritici per kg of seed. To apply the dressing, the seed is shaken with "the dressing in a closed glass flask. The seed, on'moist loam under a cover of a layer of muslin and 2 cm of moderately moist compost soil, is exposed to optimum germination con ditions for the spores for 10 days at 10C in a refrigerator.

The germination of the spores on the wheat grains,

each of which is contaminated with about 100,000 The active compounds, the concentrations of the acspores, is subsequently determined microscopically. tive compounds in the dressing, the amounts of dress- The smaller the number of spores which have germiing used and the percentage spore germination can be nated, the more effective is the active compound. seen from the following Table:

TABLE 5 Seed dressing test/bunt of wheat Concentration of active Applied compound in amount of Spore the dressing dressing germinain percent in gJkg. tion in Active compounds by weight seed percent Non-dressed. 1.

CII2-NHOS /Zn CHzNH(fi-S (known).

28 3 1 0.05 NC- N 10 1 0. 005 H 30 1 0.000 s CN \S/CN CFa S CN I N02 OzN -N CFa 30......... 10 1 0.05 O N -I| I 30 1 0. 005

31 10 1 0,005 CH3 O-C 0 -N l O. 000

Nov \SJ-CONIIZ The following further examples are set forth to illustrate, without limitation, the process for producing the active compounds according to the present invention.

trifluoromethyl-7-nitrobenzthiazole-N-oxide are dissolved in l200 ml of chloroform. To the clear solution there are added dropwise, with stirring, 100 ml (about 157g or l.l4 moles) of phosphorus trichloricle, the temperature of the reaction mixture being kept at 20 to 40C by'occasional ice cooling. After completion of dropwise addition, the reaction mixture is stirred for 4 hours at room temperature and the chloroform is subsequently distilled off in a vacuum. The oil remaining behind is made to crystallize by cooling and seeding.

The product is washed neutral with water and, for further purification, recrystallized from cyclohexane.

of 2-ethoxycarbonyl-5-trifluoromethyl-7- nitrobenzthiazole are obtained in the form of lightyellow needles of the melting point 75 76C. Yield: 76% of theory.

The following compounds were also prepared in similar manner:

2..... NC N M.l. 111F138" J-COOCzTIs 3... H C N M.P.154156 C.

SLCOOCzIh N02 4... Oil, 119 115198; M.P.35-

OzN- --N 37 C.

\SJCOOCZIIE 12.1. 108110 o./0.1 mm. F C- -N M.I.4445 C.

\SJ-COOCZHS l CR 6..... M.P. 8990 C.

COOCzHi 7... O N N M1. 102-104 G.

CIIaOOC* i" l S -COOC:IT5

FaC- |I I s -CONH2 NC ,N

\SLCONIIZ ozN *TT siCONHz FaC- -N LCONHz s Ol- -fil S -CON112 l NO 1)2N"' \/\S/ 410N112 CHaOOC- |N SLCONH'.

F3C W S CONHC4H9 F C- HT S CONI[Cal[1 l F3C T s)-CONHCH:s

M .P. 225226 C.

M.P. 268270 C.

M.I. 197-109" C.

M.P. 131-13? C M.P. 229 C.

M. l. BET-230 C.

MI. 248-250 C.

M.P. 102-103 C.

Ml. 148-150 C It will be appreciated that the instant specification and examples are set forth by way of illustration and not limitation, and that various modifications and changes may be made without departing from the spirit and scope of the present invention.

What is claimed is:

l. A substituted benzthiazole of the formula in which R is CN or a radical of the formula -COZ,

' R is halogen, nitro, trifluoromethyl, trifluor'omethoxy or a radical of the formula R is hydrogen, halogen, trifluorometh l, tri- Y fluoromethoxy, nitro, methyl, ethyl, CN or a radical of the formula n is O, l or 2, and

Y and Z each independently is hydrogen, alkyl, cycloalkyl or alkoxy with up to 6 carbon atoms, benzyl or phenyl, or a radical of the formula in which R and R each independently is hydrogen,

alkyl or cycloalkyl with up to 6 carbon atoms or one of R and R may be phenyl, or R and R together with the connecting nitrogen atom form. a pyrrolidine, piperidine or morpholine ring.

3. A compound according to claim ll wherein such compound is 2-cyano-5-nitro-7-trifluoromethylbenzthiazole of the formula O2N H N 10 i 4. A compound according to claim 1 wherein such compound is 2,5-dicyano-7-nitro'benzthiazole of the formula Ti S -CN 5. A compound according to claim 1 wherein such compound is 2-cyano-5-chloro-7-nitrobenzthiazole of the formula N 30 [1 CN 6. A compound according to claim ll wherein such compound 1s 2-cyano-4-chloro-5-nltro-7- trifluorobenzthiazole of the formula (MN N 7. A compound according to claim ll wherein such compound is 2-cyano-4,5-dichloro-7-nitrobenzthiazole of the formula J-CN I S N02 (35) 

1. A SUBSTITUTED BENZTHIAZOLE OF THE FORMULA
 2. A compound according to claim 1 in which R1 is chlorine, bromine, nitro, trifluoromethyl or -SO2-Y; R2 is methyl, ethyl, chlorine, bromine, trifluoromethyl, nitro or -CO-Z; Y and Z each independently is lower alkyl with up to 4 carbon atoms, benzyl, phenyl or
 3. A compound according to claim 1 wherein such compound is 2-cyano-5-nitro-7-trifluoromethylbenzthiazole of the formula
 4. A compound according to claim 1 wherein such compound is 2,5-dicyano-7-nitrobenzthiazole of the formula
 5. A compound according to claim 1 wherein such compound is 2-cyano-5-chloro-7-nitrobenzthiazole of the formula
 6. A compound according to claim 1 wherein such compound is 2-cyano-4-chloro-5-nitro-7-trifluorobenzthiazole of the formula
 7. A compound according to claim 1 wherein such compound is 2-cyano-4,5-dichloro-7-nitrobenzthiazole of the formula 